Granted, it is a little irritating to discover that the agenda-makers on the left look at you as though you were something they had just fished out of a clogged drain, but I wasn’t shocked. I have always just assumed that, behind closed doors, this is pretty much how the conversation goes with the liberal left.

Conservative Catholics are an inexplicably intractable barrier to their agendas, and the mystery of how such “severely backwards” folk can be a wrench in their progressive system must be a source of unending frustration to them.

I was not outraged because, as fellow American citizens, they have a constitutionally established right to be ignorant and bigoted right out loud, and to speak their mind freely, no matter how narrow and closed that mind might be.

Besides, the overarching revelation here is really no revelation at all: the die-hard insiders on the political left are really as impenetrably self-referential, agenda-driven and obtuse as they have always seemed. And they see conservatives as mostly irredeemably unenlightened pawns of outdated belief systems.

As interesting as all the ridicule and manipulative scheming contained in those emails was, for me, the piece de resistance was the reply from John Halpin, a staffer at the Clinton-allied Center for American Progress, to an email from comrade-in-arms Jennifer Palmieri, now a Clinton campaign spokesman.

Halpin says, “Excellent point. [Conservative Catholics] can throw around ‘Thomistic’ thought and ‘subsidiarity’ and sound sophisticated because no one knows what the hell they’re talking about.”

Of course Mr. Halpin has no idea what “Thomistic thought” and “subsidiarity” mean. He is a career agenda-pusher for the liberal left. I’m not sure there has ever been a group, by definition, more incapable of understanding those beautiful ideas than the high-ranking operatives in the liberal Democratic political machine.

But what, exactly, are we talking about when we use those terms, and what does it matter?

“Thomistic,” of course, refers to any idea, argument or explanation consistent with, or derived from, the thought of the great medieval philosopher theologian, St. Thomas Aquinas, irrefutably one of history’s greatest intellects.

Thomistic thought is grounded in the knowledge that the universe is brought into existence, and sustained in it, wholly by the benevolent will and infinite power of Almighty God, Himself eternally a Trinity of divine persons in one divine nature.

Following on this fact, the Thomistic worldview asserts that Man, created male and female, in the image and likeness of the Triune God, has both a divine origin (in a unique act of God’s creative will) and a divine destiny (in the Beatific Vision of the Blessed Trinity forever, in heaven). On this firm foundation rests Aquinas’ understanding of the human person as naturally possessed of inviolable dignity and inestimable worth, brought into existence for his or her own sake, with a purpose in God’s plan for the world He created.

Where the human person is concerned, the Thomistic understanding has always held that we are bound by the objective natural law, to which we are ordered for our flourishing and perfection, and for which God has given us the rational capacity to know, will and act.

Thomistic thought can be a strong antidote to a culture of poisoned ideas about the human person.

The second term Halpin mentions, subsidiarity, is a foundational principle of Catholic social and political thought. Stated simply, it is the idea that, whenever possible, problems ought to be solved, and challenges met, at the most local level possible.

Practically speaking, this means decentralizing some of the government’s power, and upholding both personal liberty, and the rights of families and communities to act in their own best interest, free from undue regulation, interference, or coercion.

It is not Libertarianism—government still has a role in shaping the citizen, and restricting some freedoms, especially where freedom is misused in a way that undermines virtue.

Subsidiarity, instead, understands government as limited to the handling of civic temporal affairs, and the legislation and intervention necessary to create and fortify conditions that promote free and virtuous citizenship. This vision of government flies in the face of the bloated, abusive, and intrusive bureaucratic juggernaut so cherished by the modern left.

Together, Thomistic thought and subsidiarity offer a compelling vision of who the human person is, and how we ought to live together in pursuit of the common good. They inform political thought aimed at building a society that acknowledges and supports free and responsible citizenship, and upholds the value of each human person, and they are seminal to the pro-life movement, religious liberty, the defense of traditional marriage, and most of the other fundamental rights, and political goods, of Western civilization.

Now, contrast the Thomistic subsidiarity of the Catholic intellectual tradition with what is revealed in the emails from Clinton’s cronies. What is immediately apparent is that these fundamentally important principles are diametrically opposed to the worldview, and policy-making, of the political left, even as both principles remain a mystery to them.

They may be ignorant of their meaning, but they are all too familiar with their effect. After all, taken together, Thomistic thought and subsidiarity stand athwart virtually every ideology embraced by the left, and countermand virtually every policy directive issued by the current administration. And therein lies the seed of their hostility.

The anthropology of the left is anti-Thomistic. They espouse a nature-denying, sex-conflating, gender-fluid exaltation of radical personal autonomy and self-definition, coupled with the assertion that the value of a given human life is always a question in play, to be decided by fill-in-the-blank-according-to-circumstances.

The social and political theory of liberal Democrats is anti-subsidiarity. They see big government as the bestower of rights, arbiter of disputes, and enforcer of values. Given the real danger that they will fail to voluntarily fall in line with the progressive agenda, ordinary citizens are not to be trusted with real freedom, nor empowered to order and direct their own lives. The federal government exists to fund—with increased tax revenue—the necessary oversight, intervention and coercion, and to impose on recalcitrant citizens the societal ideologies engineered by the political elite.

The reality we face is this: in their world, those of us who hold the principles of Thomistic thought and subsidiarity dear, are not just targets of scorn. For the left, we are targets for eradication. After all, to tell a lie you have to deny the truth. To sell a lie, you have to silence it.

Politically, financially, legally or otherwise, they mean to eliminate us. They may not “understand what the hell [we] are talking about,” but there is no mistaking that we stand in their way, and the anti-Thomistic forces marshalling against subsidiarity will brook no opposition.

The time has come to set our face to the fight, never forgetting G.K. Chesterton’s sagacious admonishment that, “the true soldier fights not because he hates what is in front of him, but because he loves what is behind him.”

As lovers of truth, and defenders of life, liberty and the pursuit of (true) happiness, we must now either act, or be acted upon. As followers of Christ, we must never fail to live and speak the truth about the human person, and we must take every opportunity to create a government that exists for the good of the citizen, lest our opponents succeed in doing the opposite.

Steve Greene is Director of Kino Catechetical Institute at the Diocese of Phoenix, and co-host, with his wife, Becky, of The Catholic Conversation radio show, which airs on Immaculate Heart Radio in Phoenix, and is podcasted on iTunes and at www.phoenixcatholicmedia.org. For the past 13 years, he has taught Catholic theology, philosophy and ethics, as well as St. John Paul II’s Theology of the Body, for a variety of institutions.